Container



y 28, 1964 4 A. s. MOJONNIER 3,142,422

- CONTAINER Filed Aug. 10, 1959 V nlllll'olllllllllllll IfllllllllllllllUnited States Patent F 3,142,422 CONTAINER Albert B. Mojonnier, Chicago,Ill., assignor to Albert Mojonnier, Inc, Franklin Park, Ill., acorporation of Illinois Filed Aug. 10, 1959, Ser. No. 832,803 3 Claims.(Cl. 222-566) This invention relates, generally, to innovations andimprovements in inexpensive, disposable containers, for liquids such asmilk. More particularly, it pertains to such cartons or containersformed of thin, membrane-like plastic sheet material.

At the present time, and for a number of years, disposable milk cartonshave been formed of wax-coated paper or paperboard. In fact, waxorparaflin-coated paper cartons are for practical purposes the only typeof disposable cartons that have been used commercially to anysubstantial extent for milk, chocolate drink, orange juice, etc.However, the waxor paraffin-coated paper milk containers are known tohave several shortcomings, in spite of which they have gained acceptancesince nothing as good was brought forth in the way of a disposablecontainer or carton for such liquids. From the standpoint of theconsumer, there are two main objections to wax or paraffin-coatedpaperboard milk cartons. One objection is the encountering of scales orflakes of paraflin in the milk. The other objection is that notinfrequently socalled leakers are encountered. Thus, almost everyone whohas purchased milk in paperboard cartons has encountered those whichleak or seep milk.

From the standpoint of the carton producer, or the dairy (since some ofthe larger dairies complete the paperboard containers from knocked-downor flattened blanks), the expense of the containers is an item andanother is the fire hazard connected with the use of molten paraffinwax. In addition, the dairy often receives complaints from customersabout wax in the milk and leaky cartons. Some dairies buy pre-formedpaperboard cartons but they are so bulky as to prevent them from beingshipped very far from the carton manufacturer and make storage costs sohigh that substantial stock-piling is prohibitive.

The idea of forming disposable milk cartons from. plastic materials hasperhaps occurred to others, but heretofore, for one reason or another, acommercial, disposable container formed of plastic, for liquids such asmilk and the like, has not been developed. Apparently, it has not beenpossible to produce such containers from plastic materials which willmeet the rigid specifications required for containers of this type, andyet which would be sulficiently inexpensive to be competitive withpaperboard containers. It is diflicult to over-emphasize the factor ofexpense. Despite their short-comings, the wax-coated, paperboard cartonsare acceptable and the dairy business is so competitive that only theleast expensive disposable carton will be purchased in any quantity.Therefore, practically speaking, the maximum price of disposable milkcartons is the price at which the paperboard cartons can be purchased.

It has been discovered in accordance with the present invention thatcontainers for liquids such as milk and formed of plastic sheetmaterials, may be made which are competitive price-wise with theWax-coated paperboard containers and which are free from the several disadvantages associated with paperboard containers. It was necessary tomake a number of departures from the features of construction present inpaperboard milk containers and other containers of this type, before theplastic containers of the present invention became possible from thepractical standpoint. Since the raw material cost of the plasticconstitutes a considerable part of the total cost 1 3,142,422 PatentedJuly 28, 1964 ice ' of the plastic cartons, the plastic that could beafforded for each carton had to be used with upmost efficiency. Hence,it was not merely a matter of substituting one material for another(i.e. plastic for wax-coated paperboard) since problems were involvedwhich were peculiar to the use of thin or membrane-like plastic sheetmaterial. Taking a one-half pint milk carton formed of polystyreneplastic by way of example, stated in another way, the problem was tofind a practical way to make such a carton out of about 5 to 6 grams ofthe plastic.

An important object of the invention is the provision of disposablecontainers for liquid such as milk which in respect to price andspecifications are at least competitive with present-day disposablecontainers for milk and the like, but which are made from thin ormembrane-like plastic sheet material.

A further important object of the invention is the provision of suchcontainers for liquids such as milk and formed of light plastic sheetmaterial, which have builtin strengthening or rigidifying features eachof which serves at least one additional function or purpose besidescontributing to the strength and rigidity of the cartons.

Another important object of the invention is the provision of containersfor liquids such as milk formed from plastic sheet material of suchover-all thinness and light weight as would not be strong enough exceptfor a particular distribution of the material through variation ofthickness between different locations in combination with certainbuilt-in strengthening or rigidifying features which also serve otherfunctions in the containers.

Another important object of the invention is the provision of improvedcontainers formed from membrane-like plastic sheet materials which canbe produced inexpensively by mass production techniques in the form oftwo mating halves which are nestable in corresponding halves so thatshipping and storage costs are minimized, and which may be assembled andsealed together on inexpensive, reliable equipment which may be readilyinstalled and easily operated at the local dairy or other filling plant.

Still another important object of the invention is the provision of animproved method of closing andsealing containers or cartons for liquidssuch as milk and formed of thin plastic sheet material.

Certain other objects of the invention will, in part, be obvious andwill, in part, appear hereinafter.

For a more complete understanding of the nature'and' scope of theinvention, reference may now be had to the with the accompanyingdrawings, wherein:

FIG. 1 is a top perspective view of a disposable container for a liquidsuch as milk, formed of thin or membrane-like plastic sheet material andconstituting one embodiment of the invention;

FIG. 2 is a top plan view of the container shown in FIG. I but with theclosure cap or seal removed;

FIG. 3 is a bottom plan view of the container shown in FIG. 1;

FIG. 4 is a vertical sectional view taken on line 4-4 of FIG. 1;

FIG. 5 is a top perspective view of a thin plastic closure or seal forthe pouring spout of the container shown in.

FIGS. 1-4;

FIG. 6 is an enlarged, detail, sectional view taken on line 6-6 of FIG.4;

FIG. 7 is a detail sectional view on line 7--7 of FIG. 2 through one ofthe indentations which assists in de-nesting; and

FIG. 8 is a detail sectional view on enlarged scale showing a modifiedform of out-turned flange or seam corresponding to a section taken online 3-8 of FIG. 2.

In the drawings, a container constituting one embodiment of theinvention is indicated generally at 5 and comprises an upper cup-likeportion 6 and a lower cup-like portion 7. The upper and lower halves 6and 7 may be formed on a quantity production basis from various plasticmaterials, particularly, thermoplastic sheeting, such as food gradepolystyrene, polyethylene, acrylics, acetate, vinyls, polyvinylchloride, nylon, or polyester base resin. High impact polystyrenecomprising a co-polymer of polystyrene and butadiene rubber constitutesa presently preferred material. This plastic is commercially availablein sheet and other forms from several suppliers including Dow ChemicalCompany and Monsanto Chemical Company.

The halves or cup-like portions 6 and 7 may be mass produced by variousknown forming techniques with commercially available productionequipment. For example, the halves may be formed from heated plasticsheeting of the proper thickness (depending on the size of the carton)either by the so-called drape-forming technique or by pressure molding.

It will be seen that the container 5, and the upper and lower halves 6and 7 thereof, are generally rectangular in configuration, both invertical and horizontal section. However, there is an absence of sharpcorners and right angle intersections in view of the preferences forrounded corners and intersections which have appreciable curvature. Thehalves 6 and 7 are tapered for nesting purposes.

The upper cup-like half 6 has a generally flat top panel portion 8having integrally formed in one corner thereof an upstanding fillingneck and pouring spout 10, this neck and spout 10 is preferably formedin two sections, there being a shallower, larger diameter base sectionor boss 11 on top of which there is a deeper, smaller diameterupstanding vertical neck portion 12, with a horizontal shoulder 13therebetween. For better closure cap sealing and retention, the neckportion 12 is formed with an intermediate groove or necked-in section 9(FIG. 6). The neck portion 12 has a pointed portion 14 at the outercorner to facilitate the pouring of the contents of the container 5. Thefilling neck and pouring spout 10 in addition to serving as such, alsoserves to add rigidity to the top panel 8 such as will withstand thecapping or sealing operation and also permit stacking of one containeron the other without damage. In the half-pint size, the base or lowerportion 11 has a projected area equal to from about 10 to 15 percent ofthe area of the panel 8 including the portion 11.

The top panel 8 and rounded shoulder portion 15 of the upper half 6 aresubstantially or appreciably thicker than the remainder of the half 6below. Thus, the side walls 16 are appreciably thinner than the shoulderportions 15. At the bottom end the side walls 16 terminate in acontinuous out-turned flange 17.

In the half-pint size the plastic sheeting prior to deformation may havea thickness of from about 0.015 to 0.02 inch. The thickness of the toppanel 8 and adjacent shoulder will be from about 0.013 to 0.018 inchwhile the flange 17 and adjacent wall portions will have a thickness offrom about 0.009 to 0.011 inch. In general, the toppanel and adjacentshoulder portions will be about 4065% thicker than the flanges andadjacent thinner portions of the side walls.

The bottom cup portions or cup-like halves 7 are generally similar tothe upper half 6 except instead of having a filling opening and pouringspout 10 they are provided with an integrally formed recess or pocketindicated generally at 18, this being generally of the same shape as theexterior of the pouring spout but sutficiently larger so that thecontainers can stack one on the other with the spouts 10 fitting in therecesses 18 without binding when the closure seals or caps are presentthereon. The lower cup-like half 7 is provided with a continuous flange19 at the upper end of the side wall or panel portions 20 which mateswith the flange 17.

It will be seen that the cup-like halves 6 and 7 are tapered slightlyaway from the mating flanges 17 and 19. This permits any desired numberof the upper halves 6 to be nested, and likewise, any desired number ofthe lower halves 7 to be nested. For example, the respective upper andlower halves may be nested together and then packaged in, say,polyethylene bags wherein they will be maintained in a clean andsanitary condition until ready for use. Then, stacks of nested upperportions and lower portions 6 and 7 can be inserted in de-nestingmachines of known type whereby an upper half and a lower half will beautomatically fed together into a machine of known type which will heatseal or otherwise secure the mating flanges 17 and 19 together into acontinuous seam around the mid-portion of the containers 5.

To facilitate de-nesting it is desirable to provide a plurality ofindentations 21 and 22 in the upper and lower halves 6 and 7 as shown inFIG. 1, an indentation 21 being shown in detail in FIG. 7. It will beseen that these indentations keep the nested halves slightly separatedwhereby they can be readily (lo-nested by machines of known type.

In order that the containers 5 may be formed inexpensively and from aminimum weight of plastic sheet material, it is highly desirable thatthe side wall portions or panels 16 and 20 be so thin adjacent theirflanges 17 and 19, respectively, that they are not strong enough toresist lateral stresses that the containers are normally subjected to,e.g., as a result of tight squeezing or lateral impact. However, theliquid-tight flange seal which is formed by the joinder of the matingflanges 17 and 19 constitutes a strong rigidifying flange around themidportion of the container which adequately resists such lateralstresses. Furthermore, this flange serves as a convenient meansforgrasping and holding the containers 5 during opening and use. Thus, theflange fits very nicely between two adjacent fingers of the hand withthe thumb being placed on the opposite side.

After the halves 6 and 7 have been de-nested they may be readily joinedtogether at the mating flanges 17 and 19 in one of several manners toform a completed carton 5. The particular technique of assembly orjoinder of the flanges 17 and 19 will depend upon a number of factorssuch as, the particular plastic of which the halves 6 and 7 are formed,the type of equipment which is available, the desired output at whichthe cartons are to be formed, the kind of liquid that is to be packagedin the finished cartons (e.g. edible or inedible), etc. When the halves6 and 7 are formed of thermoplastic material, as will usually be thecase, and as is the case when presently preferred thermoplastics such aspolystyrenes and polystyrene co-polymers are used, the flanges 17 and 19may be joined together in a permanent manner by heat sealing. Equipmentfor heat sealing plastics is commercially available in several typesincluding the type that is based on the so-called hot iron method andalso the type that is based on dielectric heating.

One version of the heat sealing method may be referred to as acombination heat and mechanical sealing. That is, in addition todepending on heat, the mating flanges 17 and 19 are also subjected tomechanical pressures such as clamping, crimping, seaming, etc. Theapplication of mechanical forces in addition to heat permits less heat(i.e. lower temperatures and/or shorter times) to be used or makesstronger flanges or seams when the same amount of heat is used.

Another technique for joining the flanges 17 and 19 together involvesthe use of a so-called heat activated cement. These cements arecommercially available for different types of plastic. They usually comedissolved or dispersed in a volatile solvent and in this form may beprinted or otherwise applied on one or both of the surfaces to bejoined, and then dried or allowed to dry. Only small amounts arerequired. When the flanges 17 and 19 are brought together after one orboth of the opposing surfaces is coated with one of these cements, uponapplication of heat from the outside of the flanges, the cement willbecome activated and the flanges will be permanently bonded together.Alternately the cement may be directly heated or activated by radiantheat or hot air, after which the flanges are promptly joined. Oneadvantage of this particular technique is that a lower degree of heat(i.e. shorter times and/or lower temperatures) is required than in thecase of straight heat sealing. Therefore, the operation can be carriedin a less carefully controlled manner in so far as the times andtemperatures are concerned.

Still another method or technique for joining the flanges 17 and 19 isthe use of a so-called solvent cement. This type of cement is actuallyin the nature of a solvent or plasticizer for the particular plasticmaterials to be joined and acts by dissolving or plasticizing the matingsurfaces of the plastic so that when they are pressed together apermanent, weld-like bond may be secured. For example, benzene is asolvent cement for polystyrene and styrene base plastics.

Still another method of joining the flanges 17 and 19 together is theuse of a so-called contact cement. These cements are also commerciallyavailable and after application to mating surfaces they will cohere whenthe surfaces are pressed together.

Those skilled in the art of fabricating plastics will readily be able toselect the one or more particular sealing or cementing techniques whichis or are best suited to a particular assembly operation.

It is highly desirable, especially when the contents are milk or otherfood drink, that the filling and pouring spout be securely sealed by ahermetic or hermetictype seal. The spout 10 lends itself to being sosealed by means of a sealing cap 25 (FIG. 5) which may be formed of ashrinkable plastic sheet material such, for example, as polyethylene(either so-called standard or conventional polyethylene formed by theso-called high pressure process and having a density of between 0.91 to0.935 gram per cubic centimeter, or so-called highdensity polyethylenewhich is formed by the Ziegler Process (low pressure process) and havinga density of 0.94 to 0.97 gram per cubic centimeter). Such a cap may beformed and applied in the warm or hot condition so as to initially fitsnugly over the neck 12 and conform to the groove 9. Upon cooling andshrinking, such a closure cap will intimately conform to the outersurface of the neck 12 including the groove 9 and form a hermatic-typeseal which resists dislodgement through normal handling. It will requirea reasonable or deliberate positive removing force to be applied to thetab 26 in order to break the seal and open the container. However, thecap 25 is tough and need not be torn or destroyed on removal, therefore,this type of seal or cap 25 has the advantage that it can be re-appliedto and retained on the pouring spout 10 in case only a portion of thecontents is used or emptied out.

While polyethylene is presently preferred for forming the caps 25, theother shrinkable plastic materials may be used including, polyethyleneterephthalate (available from E. I. du Pont de Nemours & Co. under thedesignation Mylar), nylon (described in detail in Carothers Patent2,071,250), and linear polyurethane (e.g. the condensation product of1,6-hexamethylene diisocyanate with butanediol-1,4)

While in the drawings the reinforcing flange and seam formed by joiningmating flanges 17 and 19 is a plain lateral flange, this can take or begiven various special shapes. One of these is illustrated in FIG. 8. Inthis detailed sectional view primed numbers are used to indicatecorresponding portions of the carton 5. Thus, the thin membrane-likewall of the upper half 5 is indicated at 16' and that of the lower half7 is indicated at 20'. The mating flanges are designated at 17 and 19',re-' spectively. It will be seen in FIG. 8 that the outer ends of theflanges 17' and 19' are curled or bent downwardly as indicated at 30.

It will be apparent that other configurations and special formations maybe given to the composite reinforcing flange and seam such as bycrimping the flanges so that they have a corrugated-like configuration.However, a plain or straight flange as shown in the drawings has beenfound to be adequate and to serve very satisfactorily.

In the dairy, or other filling plant, after the cartons 5 have beenformed they may be filled on known types of automatic filling machinesand then capped or sealed. The capping or sealing operation may beconveniently carried out by unwinding a narrow strip of polyethylene orother cap sealing material of appropriate width, from a spool supply,heating the end of the withdrawn portion and passing the heated end overa female die into which the material is either drawn by vacuum or forcedby positive pressure so as to conform to the die cavity. The formedclosure cap may then be automatically severed (i.e. died out) from thestrip and automatically applied to the filling neck or pouring spout 10in the warm or heated condition. Obviously, the sealing caps 25 could beformed in a separate operation, shipped in bulk to the dairy, and thenapplied in the heated condition at the time of sealing.

It was mentioned above that the cartons of the present inventionincorporate certain built-in strengthening or rigidifying features whichalso serve other functions in the container. For example, the compositeflange 17-19 formed around the waist portion of each of the containersnot only provides the means for sealing or joining the upper and lowerhalves 6 and 7 together, but it also greatly rigidifies the waistportions of the containers 5, provides a means whereby the containerscan be securely gripped with the flange being straddled by the fingers,and provides a support for filling containers if they are set down in asupporting frame.v Thus, in packaging a large number of the containers 5they may be supported on trays or divider plates formed of corrugatedpaperboard, plastic or light-weight metal having holes or openingsformed therein through which the bottoms of the containers 5 willproject with the containers being supported on the flanges or seams17-19.

The filling neck and pouring spout formations 10 in addition to servingthese primary purposes, also serve to rigidify the top panel of thecontainers and also serve to lock the containers together on stacking,by projecting into the bottom recesses 18 of superposed containers. Therecesses 0r cavities 18 not only strengthen the bottoms of thecontainers and provide for stacking of the containers by receiving thefilling neck or spouts of other containers, but these cavities also helpin the gripping of the containers, since the little finger willnaturally fit and extend into these cavities as the cartons are grasped.

The indentations 21 and 22 in addition to facilitating de-nesting, alsoreinforce the shoulder portions of the halves 6 and 7.

While use of the containers 5 for milk and other consumable liquids hasbeen featured it will be understood that they can be used as inexpensivedisposable containers for a wide variety of liquids such as, motor oil,liquid detergents, liquid laundry starch, syrups, etc.

The construction of the container lends itself to various sizes.

It will be understood that certain changes in addition to thosementioned may be made in the specific and preferred embodiment of theinvention described and shown in the accompanying drawings withoutdeparting from the spirit and scope of the invention.

What is claimed as new is:

1. A shape retaining disposable plastic container comprising, generallysymmetrical upper and lower cup-like halves of approximately equal sizeand rectangular shape and formed of thin flexible plastic material, eachcup-like half having a generally flat end panel and a side wall,

each side wall including a plurality of generally rectangular sidepanels joined to the respective end panel and to each other by smoothlyrounded corner portions, said side panels diverging relative to eachother in a direction away from the respective end panel suflicient toenable nesting of like halves after the halves are formed and prior toassembly of the halves, the end panel of the upper container half havingan integral filling and pouring spout projecting upwardly therefrom,said spout having an enlarged hollow base portion for rigidifying theend panel at the juncture of the spout therewith and a reducedupstanding neck portion, said enlarged baseportion having an internalopening sufficiently larger than outer dimension of the upper end of theneck portion to enable at least partial nesting of the spouts on likeupper halves prior to assembly of the container halves, said side panelshaving an average wall thickness substantially less than the averagewall thickness of said end panels and having insufiicient strength inthe absence of additional reinforcement to resist flexing under lateralpressures applied during normal handling of the container, said upperand lower halves having mating out-turned peripheral flanges on the endsof said side panels remote from the end panels, said flanges beingrigidly bonded together in a liquid tight reinforcing flangeseamproviding a peripheral reinforcement on the container in a zonegenerally medially between the end panels for stiffening the flexibleside.

panels in the area thereof remote from the end panels.

2. The combination of claim 1 wherein the end panels have a thicknesswhich is about 40 to 65 greater than said side panels adjacent saidflanges.

3. A shape retaining disposable plastic container comprising, generallysymmetrical upper and lower cup-like halves of approximately equal sizeand rectangular shape and formed of thin flexible plastic material, eachcup-like half having a generally flat end panel and a side wall, eachside wall including a plurality of generally rectangular side panelsjoined to the respective end panel and to each other by smoothly roundedcorner portions, said side panels diverging relative to each other in adirection away from the respective end panel sufficient to enablenesting of like halves after the halves are formed and prior to assemblyof the halves, the end panel of the upper container half having anintegral filling and pouring spout projecting upwardly therefrom, saidspout having an enlarged hollow base portion for rigidifying the endpanel at the juncture of the spout therewith and a reduced upstandingneck portion, said enlarged base portion having an internal openingsufficiently larger than outer dimension of the upper end of the neckportion to enable at least partial nesting of the spouts on like upperhalves prior to assembly of the container halves, the end panel on saidlower container half having a depression therein, the sides of whichdepression taper upwardly and inwardly for receiving the upwardlyextending filling and pouring spout of a container therebelow, said sidepanels having an average wall thickness substantially less than theaverage wall thickness of said end panels and having insuflicientstrength in the absence of additional reinforcement to resist flexingunder lateral pressures applied during normal handling of the container,said upper and lower halves having mating out-turned peripheral flangeson the ends of said side panels remote from the end panels, said flangesbeing rigidly bonded together in a liquid tight reinforcing flange seamproviding a peripheral reinforcement on the container in a zonegenerally medially between the end panels for stiffening the flexibleside panels in the area thereof remote from the end panels.

References Cited in the file of this patent UNITED STATES PATENTS2,215,268 Hirnmer Sept. 17, 1940 2,412,178 Seigh Dec. 3, 1946 2,565,316Lucas et al Aug. 21, 1951 2,641,374 Der Yuen June 9, 1953 2,695,732Tupper Nov. 30, 1954 2,752,971 Tupper July 3, 1956 2,774,993 Hagen etal. Dec. 25, 1956 2,885,105 Heyl et al. May 5, 1959 2,915,214 FrankelDec. 1, 1959 2,939,603 Young June 7, 1960 2,941,660 Tupper June 21, 19603,045,887 Caine July 24, 1962 FOREIGN PATENTS 799,643 Great Britain Aug.13, 1958

1. A SHAPE RETAINING DISPOSABLE PLASTIC CONTAINER COMPRISING, GENERALLYSYMMETRICAL UPPER AND LOWER CUP-LIKE HALVES OF APPROXIMATELY EQUAL SIZEAND RECTANGULAR SHAPE AND FORMED OF THIN FLEXIBLE PLASTIC MATERIAL, EACHCUP-LIKE HALF HAVING A GENERALLY FLAT END PANEL AND A SIDE WALL, EACHSIDE WALL INCLUDING A PLURALITY OF GENERALLY RECTANGULAR SIDE PANELSJOINED TO THE RESPECTIVE END PANEL AND TO EACH OTHER BY SMOOTHLY ROUNDEDCORNER PORTIONS, SAID SIDE PANELS DIVERGING RELATIVE TO EACH OTHER IN ADIRECTION AWAY FROM THE RESPECTIVE END PANEL SUFFICIENT TO ENABLENESTING OF LIKE HALVES AFTER THE HALVES ARE FORMED AND PRIOR TO ASSEMBLYOF THE HALVES, THE END PANEL OF THE UPPER CONTAINER HALF HAVING ANINTEGRAL FILLING AND POURING SPOUT PROJECTING UPWARDLY THEREFROM, SAIDSPOUT HAVING AN ENLARGED HOLLOW BASE PROTION FOR RIGIDIFYING THE ENDPANEL AT THE JUNCTURE OF THE SPOUT THEREWITH AND A REDUCED UPSTANDINGNECK PORTION, SAID ENLARGED BASE PORTION HAVING AN INTERNAL OPENINGSUFFICIENTLY LARGER THAN OUTER DIMENSION OF THE UPPER END OF THE NECKPORTION TO ENABLE AT LEAST PARTIAL NESTING OF THE SPOUTS ON LIKE UPPERHALVES PRIOR TO ASSEMBLY OF THE CONTAINER HALVES, SAID SIDE PANELSHAVING AN AVERAGE WALL THICKNESS SUBSTANTIALLY LESS THAN THE AVERAGEWALL THICKNESS OF SAID END PANELS AND HAVING INSUFFICIENT STRENGTH INTHE ABSENCE OF ADDITIONAL REINFORCEMENT TO RESIST FLEXING UNDER LATERALPRESSURES APPLIED DURING NORMAL HANDLING OF THE CONTAINER, SAID UPPERAND LOWER HALVES HAVING MATING OUT-TURNED PERIPHERAL FLANGES ON THE ENDSOF SAID SIDE PANELS REMOTE FROM THE END PANELS, SAID FLANGES BEINGRIGIDLY BONDED TOGETHER IN A LIQUID TIGHT REINFORCING FLANGE SEAMPROVIDING A PERIPHERAL REINFORCEMENT ON THE CONTAINER IN A ZONEGENERALLY MEDIALLY BETWEEN THE END PANELS FOR STIFFENING THE FLEXIBLESIDE PANELS IN THE AREA THEREOF REMOTE FROM THE END PANELS.